Strange runway selected for Gudauta with no (or for weak?) wind

[virgo47]

When investigating...

...it started to be obvious, that Gudauta acts strange. So I've done some wind-related investigation and the results are:

• With 0 ground wind, RWY 33 is used - this would suggest that this is the "default" runway unless the opposite wind is too strong.
• But with any wind along the runway less than ~3 m/s in 151° direction (meteo 331), the RWY 15 is used. Now THIS also suggests the runway 15 is the default one - except for no wind at all.
• I tried various crosswinds - from either side, RWY 15 is used... of course, unless 0 m/s was set. (0 speed ignores the direction, which makes sense.)

This really looks like the "default" runway for Gudauta is RWY 15 and there is a bug which surprisingly uses 33 with 0 wind.

Edited January 25, 2024 by virgo47

[Ironhand]

It would seem that 33 should be the runway used whenever possibly due to the mountains off the end of 15. A DCS instrument landing in low visibility on 15 can make you dead. Interesting that 33 isn’t almost always used.

Edited January 24, 2024 by Ironhand

[virgo47]

48 minutes ago, Ironhand said:

It would seem that 33 should be the runway used whenever possibly due to the mountains off the end of 15. A DCS instrument landing in low visibility on 15 can make you dead. Interesting that 33 isn’t almost always used.

Yeah, I'd also think 33 is preferred for landing (and no problem for takeoff as a default), those mountains are really difficult to ignore on landing. In any case, the current situation is suspicious at least. I don't understand why the default map in DCS has multiple long-standing ATC issues.

Edited January 24, 2024 by virgo47

[Ironhand]

I can confirm @virgo47 's finding. No wind and RW33 is selected. 1 & 2 m/s wind from any direction will shift you to RW15. 3 m/s and higher creating a headwind for a RW33 landing will give you RW33. Any headwind 3 m/s and higher producing a headwind for a RW15 landing will give you RW15. So the issue is the 1 & 2 m/s wind speeds. TRKs attached.

Gudauta-No Wind-RW33.trk Gudauta-Wind 151_1ms-RW15.trk Gudauta-Wind 151_2ms-RW15.trk Gudauta-Wind 151_4ms-RW33.trk Gudauta-Wind 151_6ms-RW33.trk Gudauta-Wind 330_1ms-RW15.trk Gudauta-Wind 330_2ms-RW15.trk Gudauta-Wind 330_3ms-RW15.trk Gudauta-Wind 330_6ms-RW15.trk

[virgo47]

3 hours ago, Ironhand said:

...So the issue is the 1 & 2 m/s wind speeds.

Or, the issue is RWY 33 with 0 wind. If it was 15 for 0 wind as well, Gudauta would be perfectly OK aerodrome that prefers 15 and switches to 33 when the upwind for it reaches ~3 m/s.

[Ramsay]

2 hours ago, virgo47 said:

Or, the issue is RWY 33 with 0 wind.

Negative, RWY 33 with 0 wind is consistent with the original (DCS 1.2 and prior) ATC behaviour.

The erroneous ATC behaviour (effects most maps/airports) is for 1-2 m/s head/tail winds and introduced with the initial release of DCS 2.5 (2018).

https://forum.dcs.world/topic/172761-open-beta-25-kobuleti-ndbs-without-function/?do=findComment&comment=3421379

 

Edited January 25, 2024 by Ramsay

[virgo47]

2 hours ago, Ramsay said:

Negative, RWY 33 with 0 wind is consistent with the original (DCS 1.2 and prior) ATC behaviour.

The erroneous ATC behaviour (effects most maps/airports) is for 1-2 m/s head/tail winds and introduced with the initial release of DCS 2.5 (2018).

Whow, I don't go so long back... Good point. Of course, I don't really care which one is the default as long as it works properly and consistently. My speculation seemed logical, but I'm proven wrong. Thanks for the info.

[antiload]

15 hours ago, Ironhand said:

It would seem that 33 should be the runway used whenever possibly due to the mountains off the end of 15. A DCS instrument landing in low visibility on 15 can make you dead. Interesting that 33 isn’t almost always used.

 

Yes the mountains off runway 15 are a real hazard. I don't dare try and land there at night.